Fibre composite material, in particular in the aircraft industry, such as outer skin elements for aircraft, is often produced using automated fibre placement devices, which are referred to as AFP machines. In this case, relatively narrow strips of fibres, in particular carbon fibres which are embedded in a polymer matrix, are applied to a component to be manufactured or a corresponding tool. These fibre bands are placed along a predefined path on the three-dimensionally formed tool surface.
In order to manufacture a component, a plurality of individual placing steps is necessary. During these steps, a series of placing effects can occur, such as undesired overlapping of the individual fibre bands, gaps between said fibre bands or undulations, for example. These placing effects can optionally influence the mechanical properties of the manufactured component and should therefore be identified prior to using the component.
Conventionally, AFP-manufactured components are therefore examined by personnel during production. In this case, after each fibre layer has been applied, the quality of the fibre layer made from the individual fibre bands or from the layer is visually monitored with respect to the others. This is time-consuming and labour-intensive and is not always possible with a high level of certainty, in particular in the case of carbon fibres, because of the low contrast. Therefore, gaps between bands are difficult to detect since the black carbon fibres already lie on a plurality of layers of other carbon fibres, and therefore the gaps are not apparent as far as colour is concerned.
Sensors have therefore been proposed which sense the freshly placed fibre bands at a certain lateral distance from the laying head. This is disadvantageous in that errors are not detected when curves are placed in the component surface plane in particular, since a sensor following the laying head can lie outside the region to be examined in this case. Furthermore, examination results again have to be viewed and evaluated in a complex and labour-intensive manner. The space required for sensors on the laying head is also not negligible, as a result of which the installation space of the laying head and its freedom of movement are restricted.